package demo0527;

import java.sql.*;
import java.util.Scanner;

public class LoginDemo {
    private static final String URL="jdbc:mysql://localhost:3306/userdb";
    private static final String DB_USERNAME="root";
    private static final String DB_PASSWORD="123456";
    public static void main (String[]args) throws ClassCastException, SQLException, ClassNotFoundException {
        Class.forName("com.mysql.cj.jdbc.Driver");
        Connection connection= DriverManager.getConnection(URL,DB_USERNAME,DB_PASSWORD);
        String sql ="select* from userdb where username=? and password=?";
        PreparedStatement preparedStatement= connection.prepareStatement(sql);
        Scanner scanner=new Scanner(System.in);
        System.out.println("输入用户名");
        String username= scanner.next();
        System.out.println("输入密码");
        String password= scanner.next();

        preparedStatement.setString(1,username);
        preparedStatement.setString(2,password);
        ResultSet resultSet= preparedStatement.executeQuery();
        if(resultSet.next()){
            System.out.println("登陆成功");
        }
        else {
            System.out.println("登录失败");
    }
}
}
